In a blind fish that dwells in deep, dark Mexican caves, scientists have found evidence for a long-debated mechanism of evolutionary change that is distinct from natural selection of spontaneously arising mutations, as reported this week in the journal Science.

The eyeless cavefish Astyanas mexicanus is “a special system in which we can look at evolution in action,” says article co-author William Jeffery, a senior adjunct scientist in the Eugene Bell Center for Regenerative Biology at the Marine Biological Laboratory (MBL) in Woods Hole, Mass., and a professor at the University of Maryland. The Science study was led by Nicolas Rohner and Clifford J. Tabin at Harvard Medical School’s Department of Genetics. Read more…